Three-dimensional target devices, assemblies and methods for calibrating an endoscopic camera

Abstract

The present disclosure relates to calibration target devices, assemblies and methods for use with imaging systems, such as a stereoscopic endoscope. A calibration assembly includes: a target surface extends in three dimensions with calibration markers and a body with an interface that engages an endoscope so the markers are within the field of view. A first calibration marker extends along a first plane of the target surface and a second marker extends along a second plane of the target surface. The planes are different and asymmetric relative to the field of view as seen through the endoscope. Three-dimensional targets, in particular, enable endoscopic calibration using a single image (or pair of images for a stereoscopic endoscope) to reduce the calibration process complexity, calibration time and chance of error as well as allow the efficient calibration of cameras at different focus positions.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is related to and claims priority to U.S. Patent Application No. 61 / 541,427 filed Sep. 30, 2011 16, 2011, entitled “Three-Dimensional Target Devices, Assemblies And Methods For Calibrating An Endoscopic Camera” by Morrisette, et al., the contents of which are incorporated herein by reference in their entirety and for all purposes.[0002]This application is related to U.S. application Ser. No. 12 / 415,377, filed Mar. 31, 2009, (now U.S. Patent Application Publication No. US 2010 / 0245541 A1) entitled “Targets, Fixtures, and Workflows for Calibrating an Endoscopic Camera”, the full disclosure of which is incorporated herein by reference in its entirety.BACKGROUND[0003]Minimally invasive surgical techniques are aimed at reducing the amount of extraneous tissue that is damaged during diagnostic or surgical procedures, thereby reducing patient recovery time, discomfort, and deleterious side effects. As a consequence, the average ...

AI Technical Summary

Benefits of technology

The patent provides improved target devices, assemblies, and methods for calibrating, adjusting color balance, and running diagnostic tests on imaging devices, particularly endoscopes. These target devices have a three-dimensional surface that can be used to calibrate the endoscope quickly and accurately, reducing the chance of errors and improving the quality of the imaging. The target devices can be easily aligned with the endoscope and can be used at different focus states. The movement of the target device's interface relative to the base can identify the endoscope's characteristics and align its field of view with the target surface. The target devices have a resilient bushing and an axial stop to ensure precise alignment. Overall, the provided target devices and methods make the calibration process easier, faster, and more reliable.

Problems solved by technology

Existing calibration devices and methods suffer from a number of problems.

For example, properly positioning and orienting the calibration pattern of image features of some prior art calibration targets relative to the imaging device may not be intuitive, and it may therefore be difficult for non-technical persons to obtain the desired calibration.

Additionally, since human hands are not very steady, holding the camera or target freehand typically induces motion blur, while having to resort to a large, benchtop endoscopic support might render the system too unwieldy for regular use in the field.

Some methods also require manually designating characteristics of the pattern in the resulting images, which may also lead to errors in calibration.

Where functional degradation that does not rise to an intolerable level has occurred, an endoscopic imaging system may continue to be used due to a lack of knowledge on the part of the user that any functional degradation has occurred.

Such latent functional degradation may have significant detrimental consequences in a critical image-guided procedure, such as many minimally invasive surgeries.

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